After each start Shih Tao asks you in a dialog for your licence code. The licence code do you get if you register Shih Tao.
If you want to start Shih Tao as evaluation copy - this is allowed for four weeks - you have to choose the command button: I want to try. Then choose Ok in the next message box, if you agree.
If you want to order Shih Tao, choose the command button: Print order form.
In the registred version, you have to enter your licence code only once, when you first start Shih Tao.